Intake and exhaust valve seat width

[pittsburghracer]

And off we go. Now that I have the ability to use some custom cutters when cutting valve seats it’s time to order some more cutters. I’ve been limited with my Neyway cutters of going 60-45-30-15 by hand I’m looking forward to cutting set widths. For now I’m staying away from anything that isn’t a 45 degree seat because I know for me that angle works ok. I downloaded a conversion chart on my phone as most of the cutters come in MM’s. So what width seat do you like on the intake seat. How about the exhaust. Let’s stick with 1000’s (example .040 intake, .060 exhaust)

 

[MOPAROFFICIAL]

And off we go. Now that I have the ability to use some custom cutters when cutting valve seats it’s time to order some more cutters. I’ve been limited with my Neyway cutters of going 60-45-30-15 by hand I’m looking forward to cutting set widths. For now I’m staying away from anything that isn’t a 45 degree seat because I know for me that angle works ok. I downloaded a conversion chart on my phone as most of the cutters come in MM’s. So what width seat do you like on the intake seat. How about the exhaust. Let’s stick with 1000’s (example .040 intake, .060 exhaust)

Great topic.

Yes, seat width can change it all.
I had been using .060 wide angles for many years and recently am trying .030 45*, .200 60* and .025 30*.
The seat is pushed out more to the edge of the valve face. I have not tried back cutting that version yet to see if it helps or just speeds it up too much.
One thing is that if I go 5 angle ,75,60,45,30,15... they like each to be the same width .050-.065 ..or it gets away from itself, has turbulent lifts.
Do you use the entire face or?

 

[MOPAROFFICIAL]

One thing is... you want a healthy margin on the valve....or it will hurt the flow BAD.
Heres a used up pos ferrea 5000 ground to its nutsack...vs a new engine pro
The other pis is playing with the 75 widths

 

[pittsburghracer]

Ya that valve is shot. Lol. When I cut my seats with Neway cutters I always used a wide seat set by eye. With my new cutter (number 62) it has a 1mm 45 and man it looks skinny to me but I guess I will get used to seeing it on my intake seats.

 

[Rat Bastid]

On a 45 I never go wider than .040 (thats 1mm for the guys who think it’s better) and I use a 7-8 degree back cut on the valve right up to the 45. Unless the cam is too big for the application, or the port is already too big. Then I keep the BC at about .060 to help with reversion.

Will the cutter you posted get you 88% throat?

 

[pittsburghracer]

On a 45 I never go wider than .040 (thats 1mm for the guys who think it’s better) and I use a 7-8 degree back cut on the valve right up to the 45. Unless the cam is too big for the application, or the port is already too big. Then I keep the BC at about .060 to help with reversion.

Will the cutter you posted get you 88% throat?

Not sure yet. I’m used to setting the throat by hand.

 

[Rat Bastid]

Not sure yet. I’m used to setting the throat by hand.

Yeah, I should have asked can you get there without wiping out some of all of the bottom cut. IMO the more sharp edges (for the intake port and valve) the better.